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water zones. Based on work in the Sacramento Valley from the early 1900s, it is estimated that under "natural' conditions, ground water contains nitrate at concentrations no more then about 13.5 mg/L-NO3 (3 mg/L-N). Nitrate may be increasing in areas with concentrations of 24.75 mg/L-NO3 (5.5 mg/L-N) or more (Hull, 1984). The US EPA has set the Maximum Contaminant Level (MCL) for nitrate as NO3 at 45 mg/L (10 mg/L-N). Although nitrate is a naturally-occurring compound necessary for plant growth, it can cause health problems when present at high levels in drinking water. The most common health effect of nitrates in water is methemoglobinemia, or blue baby syndrome, which results in reduced oxygen supply to vital tissues. Pregnant women and certain others can also develop methemoglobinemia. Symptoms include a bluish color of the skin, as well as headache, dizziness, weakness, and difficulty breathing. Ingestion of high levels of nitrates over time can also lead to gastric problems. DBCP was not detected in the sample. DBCP is a nematocide and soil fumigant for vegetables and grapes. It is known to cause male reproductive effects and is classified as a probable human carcinogen. Most domestic use of DBCP was discontinued in 1977 through 1979. The US EPA set the MCL at 0.2 parts per billion (ppb, equivalent to pg/L) because it believes that given present technology and resources, this is the lowest level to which water systems can reasonably be required to remove this contaminant should it occur in drinking water. The Maximum Contaminant Level Goal (MCLG) for DBCP is zero. In addition, Mr. Tavares provided analytical results from previous water sampling conducted at the domestic well on July 1, 2013. Nitrate was detected at 110 ppm (mg/L-NO3) on this date. The discrepancy in results may result from seasonal fluctuation of ground water flow. Both results are well above the MCL. The laboratory analytical results are attached as Appendix 5 of this report. Soil Profile and Geologic Information The Site is mapped on the Geologic Map of California, San Jose sheet (Rogers, 1966). It is depicted within a map unit of recent Great Valley fan deposits (Plate 7). The surface and near surface soils located at the Site are reported by the USDA Web Soil Survey to be composed of Delhi loamy sand, Honcut sandy loam, and Tinnin loamy coarse sand (Plate 8) (USDA, 2014). The table below presents some selected properties of these soils: LOGE 1328 Page 5